From a2af23b7d7cb0de89570e97da84f6fb642e990a4 Mon Sep 17 00:00:00 2001
From: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Date: Mon, 4 Apr 2016 02:53:06 +0530
Subject: [PATCH] Btrfs: __btrfs_buffered_write: Pass valid file offset when
releasing delalloc space
The delalloc reserved space is calculated in terms of number of bytes
used by an integral number of blocks. This is done by rounding down the
value of 'pos' to the nearest multiple of sectorsize.
The file offset value held by 'pos' variable may not be aligned to
sectorsize and hence when passing it as an argument to
btrfs_delalloc_release_space(), we may end up releasing larger delalloc
space than we originally had reserved.
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---
fs/btrfs/file.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 751daacd268d8..af059c44684dc 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1696,7 +1696,9 @@ static noinline ssize_t __btrfs_buffered_write(struct file *file,
btrfs_end_write_no_snapshoting(root);
btrfs_delalloc_release_metadata(inode, release_bytes);
} else {
- btrfs_delalloc_release_space(inode, pos, release_bytes);
+ btrfs_delalloc_release_space(inode,
+ round_down(pos, root->sectorsize),
+ release_bytes);
}
}